What does MS, RD stand for? (srs)

Writing a paper and need to figure out what the hell this stands for. I can't figure it out it's been a long day. You know when a magazine or something says John Doe, MS, RD, states that Miscing is great for the heart. What do those stand for?

Writing a paper and need to figure out what the hell this stands for. I can't figure it out it's been a long day. You know when a magazine or something says John Doe, MS, RD, states that Miscing is great for the heart. What do those stand for?

Without context it could mean a thousand things. But I'm thinking Master of Science, and Registered Dietitian? That is, if your context involves food?